Segmented friction member assembly for brake or clutch

ABSTRACT

A segmented friction member assembly for a disc type brake or clutch in which straps extend around peripheral portions of segmental facing members and segmental heat absorbing bodies to hold the assembly together. The straps connect adjacent facing members in a manner such that there is a balanced reaction to forces exerted on said facing members. The straps also resist wear of the friction member and the torque keys in the area where the friction member is keyed to the rotating or nonrotating structure for transmitting torque thereto.

United States Patent [191 Thrower et a1.

[54] SEGMENTED FRICTION MEMBER ASSEMBLY FOR BRAKE OR CLUTCH Inventors:Arthur J. Thrower; Marvin E. V

Hotchklss, both of Troy, Ohio Assignee: The B. F. Goodrich Company, New

York, N.Y.

Filed: Sept. 30, 1971 Appl. No.: 185,238

US. Cl ..l92/l07 R, 188/218 XL Int. Cl. ..F16d 65/12, Fl6d 13/64 Fieldof Search ..192/107 R, 218 XL References Cited UNITED STATES PATENTS3,403,759 10/1968 'Holcomb ..192/l07R 3,618,729 11/1971 Ely ..l92/l07R 1Apr. 3, 1973 3,295,641 1/1967 Eaton et al ..i88/218 XL 3,483,953 12/1969Bender ..-..192/1Q7 3,599,766 8/1971 Ely ..l92/l07 R PrimaryExaminer-Benjamin W. Wyche Attorney-John D. Haney 57 ABSTRACT Y Asegmented friction member assembly for a disc type brake or clutch inwhich straps extend around peripheral portions of segmentalfacing'members and segmental heat absorbing bodies to hold the assemblytogether. The straps connect adjacent facing members in a manner suchthat there is a balanced rea'ction'to forces exerted on said facingmembers. The straps also resist wear of the friction member and thetorque keys in the area where the friction member is keyed to therotating or nonrotating structure for transmitting torque thereto.

17 Claims, 8 Drawing Figures BACKGROUND OF THE INVENTION This inventionrelates to disc type brakes or clutches and particularly to the annularfriction disc members which engage other friction disc members duringoperation of the brake or clutch. These friction disc members may have acore of heat absorbing material which has been referred to as the heatsink element and be sandwiched between facing members of wearresistantmaterial. These facing members may carry a friction lining for engagingthe friction lining of another disc member.

It has been found that when the core of heat absorbing material is asolid annular body, there may be problems with thermal warpage andcracking and accordingly the friction disc assemblies have beensegmented to reduce the thermal stresses and eliminate the thermalfatigue cracks which have been especially prevalent in the friction discrotor members of'a brake or clutch. The use of segmented friction discparts also reduces the cost of replacing parts which may be veryexpensive because of the cost of the materials used for the heat sinkelements.

It will be evident that with a segmental friction disc member, thesegments must be held together in a manner in which they will maintaintheir alignment and each segment must be supported to resist the variousforces resulting from the frictional engagement of one disc member withan adjacent disc member and the transmission of the torque to a torquetube or to a wheel. It has been found that where the segments arefastened together in the heat-swept area where the greatest thermalexpansion and shrinkage take place, forces are set up which exertundesirable stresses on the facing members and the segmental heat sinkbodies between the facing members. This is especially true where holesmust be drilled in the heat sink bodies interfering with the thermalflow and the thermal expansion of these bodies.

It has also been found that special guards or wear-resisting clips havebeen necessary to protect the heat sink bodies and the torque keysfromundesirable wear causing early replacement of parts and detractingfrom the performance of the brake or clutch.

SUMMARY OF THE INVENTION According to this invention, an annularsegmental friction member is provided in which the facing members areheld in position on the opposite faces of the heat sink bodies by strapmembers extending around the outer periphery of the heat sink bodies andover the facing members. With this construction, it is not necessary tohave holes in the heat sink body, especially in the heat-swept area, andtherefore uninterrupted thermal flow and freedom from thermal expansionmay be obtained. Each of the facing members may have radially, outwardlyextending lugs in engagement with the ends of the strap members so thatthe forces exerted by the lug of one facing member against the strap maybe conveyed to the lug of an adjacent facing member through the strapmember to balance the reactions to the forces in each facing member.This is especially true with respect to the forces tending to turn thefacing members relative to the heat sink bodies. The segmental facingmembers have side edges which are offset from the side edgesof the heatsink bodies providing an overlapping construction for holdingtheassembly together and keeping it in alignment.

Indentations at the peripheral corners of the segmental heat sink bodieshave radially extending edges around which the strap members extend.These radially extending edges at opposite ends of the heat sink. bodieshave an undercut, converging relationship which is desirable forresisting radial movementsof the strap members off of the heat sinkbodies. Flanges on the ends of the straps overlie the peripheral edgesof the heat sink bodies at the corners and also maintain the strapmembers in position.

Resistance to wear at the indentations is provided by the overlappingstrap members at the ends which bear against the wheel drive keys andserve to reduce wear on the keys also.

The strap members may be de'tachably connected at a position spaced fromthe ends for ease of maintenance and replacement. In one modification,the ends may be fastened together by rivets which extend through thelugs of the facing members and the heat sink bodies at a positionoutside the heat-swept area.

The accompanying drawings show one preferred form and a modificationmadein accordance with and embodying this invention and which arerepresentative of how this invention may be practiced.

BRIEF DESCRIPTION OF TI-IIE DRAWINGS In the drawings: FIG. 1 is asideelevation of a part of an annular disc assembly (shown in solid lines),certain parts being broken away and illustrated in torque drivingengagement with a related part which in this example may ,be a rotatablewheel, the sides of'which. are representedby the chain-dotted lines. I i

FIG. 2 is an enlarged, detailed sectional view .of the disc assembly,taken along the plane of line Z-Zof FIG. 1.

invention, certain parts being broken away and illustrated intorquedriving engagement with a related part which in this example may be arotatable wheel, the

sides of which are represented by the chain-dotted lines.

FIG. 6 is an enlarged, detailed sectional view of the disc assemblytaken along the plane of line 6-.6 of FIG.

- FIG. 7 is an enlarged, detailed view of the. disc assembly taken alongthe plane of line 7-7 of FIG..5.

FIG. 8 is an enlarged fragmentary, detailed view taken along the planeof line8-8 of FIG. 5.

DETAILED DESCRIPTION Heat sink body side edges 12 of one of the heatsink bodies 11 are closely spaced to the heat sink body side edges 12 ofadjacent heat sink bodies permitting room for thermal expansion andcontraction. The heat sink bodies 11 have outer peripheral edges 13 andinner peripheral edges 14 with indentations 15 at the radially outercorners where the side edges 12 and outer peripheral edges 13 cometogether.

Strap members 16, which may be of steel bands, extend circumferentiallyof the friction member at the outer peripheral edges 13 of the heat sinkbodies and around the indentations l5. Ends 17 of the strap members 16are wrapped around the indentations of the heat sink bodies 11 and havecircumferentially extending flanges 18 shown more clearly in FIG. 4 foroverlapping the outer peripheral edges 13 of the heat sink bodies 11 tohold the strap members in position. The ends 17 of the strap members andthe flanges 18 also provide a wear-resistant surface for engagement withdriving lugs or splines 19 of a rotating part such as wheel 23.

The arcuate heat sink bodies 11 have radially extending faces 24 whichare covered on opposite sides by a series of facing members 25. Each ofthe facing members 25 has a pair of radially, outwardly extending lugs26 which are spaced apart a distance equal to approximately the width ofthe splines 19 for embracing the splines in driving relationship. Thestrap members 16 are wrapped around the lugs 26 and hold the facingmembers 25 against the faces 24 of the heat sink bodies 11.

Radially extending edges 27 of the lugs 26 and radially extending edges28 at the indentations 15 of the heat sink bodies 11 around which theends 17 of the strap members 16 are wrapped are undercut and extendtowards the center of the friction member 10 on a converging pathproviding resistance to radially outward movement of the strap membersduring operation. This may be accomplished by making these edges 27 and28 radial or by increasing the angle so that extensions of the edgeswould converge short of the center of the friction member 10.

As shown in FIGS. 1 and 3, additional fasteners such as rivets 30 mayextend through the facing members 25 at positions radially inward of thestrap members 16 for holding the facing members against the faces 24 ofthe heat sink bodies 11. Preferably, the rivets 30 are located inpositions where they do not pass through the heat sink bodies 11 butpass between them at the side edges 12. Recesses 31 in the side edges 12may be provided for receiving torque buttons 35 which may beresistance-welded to the facing members 25 and through which the rivets30 extend.

The facing members 25 may be of steel or other wear-resistant materialand, as shown in this embodim'ent,'carry friction linings 36 which maybe of material of the type described and set forth in United States Pat.No. 2,966,737 of R. E. Spokes et al. The friction linings 36 coverarcuate areas of the facing members 25 which are engageable withopposing faces of associated brake or clutch structures upon axialmovement of the friction member 10relative to the other brake parts notshown. In theembodiment shown, the friction member is a rotor androtates with the wheel and therefore would" move axially into engagementwith a stator mounted on a torque tube which may be attached to a wheelsupporting structure.

As shown in FIG. 1, the facing members 25 have radially extending sideedges 37 which are arcuately offset from the side edges 12 of the heatsink bodies 1 1, providing an overlapping of the heat sink bodies by thefacing members with the assembly being held together by the strapmembers 16 which are located outwardly of the heat-swept area of thefriction member 10 and therefore are not subject to the thermalexpansion and contraction found in the areas covered by the frictionlinings 36. The strap members 16 have overlapping end portions 38 whichmay be detachably connected at the side as by welding or spot rivetingso that assembly and disassembly may be accomplished with a minimum oftime and labor.

During operation of the friction member, the friction linings 36 aremoved axially into engagement with opposing faces of stators generatingheat and exerting turning forces on the facing members 25 about thetorque buttons 35 which is resisted by the lugs 26 exerting forces onthe strap members 16 at one end. These forces are reacted by the lugs 26on the strap members 16 and in turn on splines 19. In this manner, theturning forces of the facing members 25 are totally reacted providing abalanced construction. The main force due to torque is transmitted fromthe facing members 25 to the heat sink bodies 11 through the torquebuttons 35 and then to the splines 19. The torque buttons 35 alsoprevent relative movement between adjacent heat sink bodies 1 1.

Referring to FIGS. 5, 6, 7 and 8, a modification of the invention isshown in which an annular friction member 40 has a plurality ofsegmental, arcuate, heat sink bodies 41 disposed in end-to-endrelationship forming an annulus. Each of the heat sink bodies 41 hasradially extending side edges 42 at the ends which are spaced from theradially extending side edges of adjacent heat sink bodies. The heatsink bodies 41 also have outer peripheral edges 43 and inner peripheraledges 44 which are curved to conform with the curvature of the annulus.

At the outer corners where the side edges 42 and outer peripheral edges43 would intersect, the heat sink bodies 41 have indentations 45 aroundwhich strap members 46 are wrapped and extend circumferentially betweenthe indentations and over the outer peripheral portions of the heat sinkbodies. Each of the strap members 46 has ends 47 wrapped around the heatsink bodies 41 at the indentations 45 and also circumferentiallyextending lips or flanges 48 overlapping the outer peripheral edge 43 atthe corners of the indentations 45. These strap ends 47 and flanges 48are positioned for engagement with splines 49 of a wheel 53 fortransmitting torque and providing resistance to wear at this area sincethe strap members 46 are preferably of steel or other wearresistantmaterial. I

The heat sink bodies 41 have radially extending faces 54 covered byaseries of facing members 55 which are also arcuate segments disposed inend-to-end relationship around the friction member 40 forming an annuluson each side of the heat sink bodies 41. Each of the facing members 55has a pair of circumferentially, spacedapart lugs 56 extending radiallyoutwardly from the facing members and underlying the strap members 46 atpositions approximately midway between the ends 47 of the strap members.Fasteners such as rivets 57 extend through holes 58 in the lugs andthrough holes 59 in the heat sink bodies 41 for clamping the lugs 56 ofadjacent facing members together and also fastening end portions 60 ofthe strap members 46. The rivets 57 tend to hold the strap members 46 inposition as do the radially extending edges 61 of the indentations 45.These edges 61 are undercut and converge towards the center of theannular friction member 40 providing an undercut edge at each of theends 47 of the strap members 46 resisting radially outward movement ofthe ends at these positions. The flanges 48 also limit the radiallyinward movement of the strap members 46 and therefore provide a stablestructure.

The side edges '42 of the heat sink bodies 41 may have recesses 65 forreceiving sleeves 66 and torque buttons 68 which may beresistance-welded to the inner faces of facing members 55. Rivets 67extend through the torque buttons 68 for holding the facing members 55together at a position radially inward from the strap members 46'. Therivets 67 pass through the facing members 55 but pass between the sideedges 42 of the heat sink body 41 in the recesses 65 to reduce anythermal stresses caused by holes in the heat sink bodies and providingbetter thermal flow of the heat in the heat sink bodies 41.

The friction member 40, which in this case is a rotor, is movableaxially along the splines 49 into engagement with the radially'extendingfaces of other associated brake or clutch parts, as for instance, astator, and a friction lining 69 may be adherred to the facing members55 for providing the desired resistance to turning.

As shown in FIG. 5, each of the facing members 55 has radially extendingside edges 70 at the ends of each arcuate segment which are spaced fromthe side edges of the adjacent facing members. The facing members 55 arein overlapping relationship with the heat sink.

bodies 41 and the side edges 42 of the heat sink bodies arecircumferentially spaced and offset from the side edges 70 of the facingmembers.

In operation, the frictional forces tending to turn the facing members55 are totally reacted through the rivets 57 connecting the lugs 56 ofadjacent facing members and the forces are transmitted from the facingmembers to the splines 49 through the heat sink bodies 41 and strapmembers 46 in a manner which places stress on the portions of the heatsink bodies radially outward of the heat-swept area in the location ofthe friction linings 69. The rivets 67 in this area provide for holdingthe facing members together and the main force due to torque istransmitted from the facing members 55 to the heat sink bodies 41through the torque buttons 68 and then to the splines 49.

We claim:

1. An annular segmental friction member of a brake or clutch mechanismcomprising a plurality of arcuate heat sink bodies of heat absorbingmaterial in end-toend adjacent relationship, said heat sink bodieshaving radially extending faces for moving toward and away from opposingfaces of an associated brake or clutch members holding said facingmembers on said heat sink.

bodies, each of said strap members extending circumferentially of saidfriction member and completely around one of said heat sink bodies andover one of said facing members whereby the facing members are heldbetween the girdling strap member and the heat sink body.

the outer peripheral edges of said heat sink bodies and radially outwardof the heat-swept area of said friction member.

3. An annular friction member according'to claim 2 wherein said facingmembers have radially outwardly extending lugs disposed between saidstrap members and said heat sink bodies whereby saidfacing members areheld against said heat sinkbodies.

4. An annular friction member according to claim 2 wherein said heatsink bodies have indentations at the radially outer corners forreceiving radially inward extending members of an associated brake orclutch structure for transmitting torque and said strap members extendaround said indentations for protecting said heat sink bodies and saidfacing members fromwearing forces.

5. An annular friction member according to claim 4 over which said strapmembers extend and said edges" converge toward the center of saidfriction member whereby the strap member extending around said edges isretained against radial movement.

7 An annular friction member according to claim wherein said facingmembers have radially, outwardly extending lugs extending between saidheat sink bodies and said strap members at said indentations and theedges of said lugs have the same slope as said radially extending edgesof said indentations for retaining said strap members on said heat sinkbodies and said facing members.

8. A friction member for a brake or clutch compris-- ing heat sinkbodies, each with two side edges, an outerperipheral edge, an innerperipheral edge, and radially extending faces for moving toward or awayfrom opposing faces of an associated brake or clutch structure, saidheat sink bodies being assembled with their side edges in end-to-endadjacent relationship to form anannulus, a series of wear-resisting,segmental facing members arranged with adjacent side edges todefine anannulus overlying said radially extending faces of said annular assemblyof heat sink. bodies to cover said radially extending faces andfrictionally engage said opposing faces of said associated brake orclutch structure, the side edges of said facing members in said seriesbeing circumferentially offset from the correspond ing, underlying sideedges of the heat sinkbodies so that each facing member overlaps theadjoining side edges of two underlying heat sink bodies, strap membersextending circumferentially of said friction member, over said faeingmembers and around said heat sink bodies, each of said strapmembersoverlying two of said facing members and one of said heat sink bodiesfor holding said friction members together.

9. A friction member according to claim 8 wherein each of said strapmembers is located at said outer peripheral edge of each of said heatsink bodies and said facing members have radially, outwardly extendinglugs held between said strap members and said heat sink bodies.

10. A friction member according to claim 9 wherein said lugs of each ofsaid facing members are at circumferentially spaced-apart positions andone of said lugs extends between one of saidstrap members and one ofsaid heat sink bodies and another of said lugs extends between anadjacent heat sink body and another of said strap members.

1 l. A friction member according to claim 10 wherein said facing membersoverlie said radially extending faces on both sides of said heat sinkbodies and fastening means extend between the facing members on oppositesides of each of said heat sink bodies, said fastening means beinglocated between the adjoining side edges of adjacent heat sink bodies.

12. A friction member according to claim 1 1 wherein each of said heatsink bodies has recesses in the side edges, torque buttons mounted onsaid facing members and disposed insaid recesses for transmitting themain force due to torque from the facing members to said heat sinkbodies and restricting relative movement between adjacent heat sinkbodies..

13. An annular segmental friction member of a brake or clutch mechanismcomprising a plurality of arcuate heat sink bodies of heat absorbingmaterial in end-toend adjacent relationship, said heat sink bodieshaving radially extending faces for moving toward and away from opposingfaces of 'an associated brake or clutch structure, facing membersoverlying said radially extending faces for engagement with saidopposing faces for transmitting torque, strap members located at theouter peripheral edges of said heat sink bodies and radially outward ofthe heat-swept area of said friction member for holding said facingmembers on said heat sink bodies, each of said strap members extendingcircumferentially of said friction member around one of said heat sinkbodies and each of said facing n iembers having a pair of radiallyoutwardly extending lugs at circumferentially spaced-apart positions,one of said pair of lugs extending between one of said strap members andone of said heat sink bodies whereby said facing members are heldagainst said heat sink bodies.

14. An annular segmental friction member of a brake or clutch mechanismcomprising a plurality of arcuate heat sink bodies of heat absorbingmaterial in end-toend adjacent relationship, said heat sink bodieshaving radially extending faces for moving toward and away from opposingfaces of an associated brake or clutch I structure, facing membersoverlying said radially extending faces for engagement with saidopposing faces for transmitting torque and strap members holding said,

facing members on said heat sink bodies, said strap members beinglocated at the outer peripheral edges of said heat sink bodies andradially outward of the heatswept area of said friction member andhaving circumferentially extending flanges at the ends for overlappingsaid heat sink bodies and said facing members to resist wear andposition said strap member on said outer peripheral edges of said heatsink body, each of said strap members extending circumferentiall of saidfrictron member around one of said heat Sll'l bodies and over one ofsaid facing members whereby the facing members are held between thestrap member and the heat sink body.

15. An annular friction member according to claim 14 wherein said strapmembers are detachably connected at a position spaced from the ends ofsaid heat sink bodies where said strap members wrap around the radiallyextending edges of said heat sink bodies.

16. An annular segmental friction member of a brake or clutch mechanismcomprising a plurality of arcuate heat sink bodies of heat absorbingmaterial in end-toend adjacent relationship, said heat sink bodieshaving radially extending faces for moving toward and away from opposingfaces of an associated brake or clutch structure, facing membersoverlying said radially extending faces for engagement with saidopposing faces for transmitting torque and strap members holding saidfacing members on said heat sink bodies, said strap members beinglocated at the outer peripheral edges of said heat sink bodies andradially outward-of the heatswept area of said friction member and at aposition spaced from the ends of said heat sink bodies where said strapmembers wrap around the radially extending edges of said heat sinkbodies, said strap members being detachably connected to said heat sinkbodies by fasteners extending through said strap members and said heatsink bodies and each of said strap members extending circumferentiallyof said friction member around one of said heat sink bodies and over oneof said facing members whereby the facing members are held between thestrap member and the heat sink body.

17. An annular friction member according to claim 16 wherein said facingmembers have radially, outwardly extending lugs disposed between saidstrap members and said heat sink bodies at said positions spaced fromthe ends of said heat sink bodies and said fasteners extend through saidlugs.

1. An annular segmental friction member of a brake or clutch mechanismcomprising a plurality of arcuate heat sink bodies of heat absorbingmaterial in end-to-end adjacent relationship, said heat sink bodieshaving radially extending faces for moving toward and away from opposingfaces of an associated brake or clutch structure, facing membersoverlying said radially extending faces for engagement with saidopposing faces for transmitting torque and continuous girdling strapmembers holding said facing members on said heat sink bodies, each ofsaid strap members extending circumferentially of said friction memberand completely around one of said heat sink bodies and over one of saidfacing members whereby the facing members are held between the girdlingstrap member and the heat sink body.
 2. An annular segmental frictionmember according to claim 1 wherein said strap members are located atthe outer peripheral edges of said heat sink bodies and radially outwardof the heat-swept area of said friction member.
 3. An annular frictionmember according to claim 2 wherein said facing members have radiallyoutwardly extending lugs disposed between said strap members and saidheat sink bodies whereby said facing members are held against said heatsink bodies.
 4. An annular friction member according to claim 2 whereinsaid heat sink bodies have indentations at the radially outer cornersfor receiving radially inward extending members of an associated brakeor clutch structure for transmitting torque and said strap membersextend around said indentations for protecting said heat sink bodies andsaid facing members from wearing forces.
 5. An annular friction memberaccording to claim 4 wherein said facing members have radially,outwardly extending lugs disposed between said heat sink bodies and saidstrap members at said indentations whereby forces tending to rotate saidfacing members are resisted by said lugs engaging said radially inwardextending members.
 6. An annular friction member according to claim 4wherein said indentations have radially extending edges over which saidstrap members extend and said edges converge toward the center of saidfriction member whereby the strap member extending around said edges isretained against radial movement.
 7. An annular friction memberaccording to claim 6 wherein said facing members have radially,outwardly extending lugs extending between said heat sink bodies andsaid strap members at said indentations and the edges of said lugs havethe same slope as said radially extending edges of said indentations forretaining said strap members on said heat sink bodies and said facingmembers.
 8. A friction member for a brake or clutch comprising heat sinkbodies, each with two side edges, an outer peripheral edge, an innerperipheral edge, and radially extending faces for moving toward or awayfrom opposing faces of an associated brake or clutch structure, saidheat sink bodies being assembled with their side edges in end-to-endadjacent relationship to form an annulus, a series of wear-resisting,segmental facing members arranged with adJacent side edges to define anannulus overlying said radially extending faces of said annular assemblyof heat sink bodies to cover said radially extending faces andfrictionally engage said opposing faces of said associated brake orclutch structure, the side edges of said facing members in said seriesbeing circumferentially offset from the corresponding, underlying sideedges of the heat sink bodies so that each facing member overlaps theadjoining side edges of two underlying heat sink bodies, strap membersextending circumferentially of said friction member, over said facingmembers and around said heat sink bodies, each of said strap membersoverlying two of said facing members and one of said heat sink bodiesfor holding said friction members together.
 9. A friction memberaccording to claim 8 wherein each of said strap members is located atsaid outer peripheral edge of each of said heat sink bodies and saidfacing members have radially, outwardly extending lugs held between saidstrap members and said heat sink bodies.
 10. A friction member accordingto claim 9 wherein said lugs of each of said facing members are atcircumferentially spaced-apart positions and one of said lugs extendsbetween one of said strap members and one of said heat sink bodies andanother of said lugs extends between an adjacent heat sink body andanother of said strap members.
 11. A friction member according to claim10 wherein said facing members overlie said radially extending faces onboth sides of said heat sink bodies and fastening means extend betweenthe facing members on opposite sides of each of said heat sink bodies,said fastening means being located between the adjoining side edges ofadjacent heat sink bodies.
 12. A friction member according to claim 11wherein each of said heat sink bodies has recesses in the side edges,torque buttons mounted on said facing members and disposed in saidrecesses for transmitting the main force due to torque from the facingmembers to said heat sink bodies and restricting relative movementbetween adjacent heat sink bodies.
 13. An annular segmental frictionmember of a brake or clutch mechanism comprising a plurality of arcuateheat sink bodies of heat absorbing material in end-to-end adjacentrelationship, said heat sink bodies having radially extending faces formoving toward and away from opposing faces of an associated brake orclutch structure, facing members overlying said radially extending facesfor engagement with said opposing faces for transmitting torque, strapmembers located at the outer peripheral edges of said heat sink bodiesand radially outward of the heat-swept area of said friction member forholding said facing members on said heat sink bodies, each of said strapmembers extending circumferentially of said friction member around oneof said heat sink bodies and each of said facing members having a pairof radially outwardly extending lugs at circumferentially spaced-apartpositions, one of said pair of lugs extending between one of said strapmembers and one of said heat sink bodies whereby said facing members areheld against said heat sink bodies.
 14. An annular segmental frictionmember of a brake or clutch mechanism comprising a plurality of arcuateheat sink bodies of heat absorbing material in end-to-end adjacentrelationship, said heat sink bodies having radially extending faces formoving toward and away from opposing faces of an associated brake orclutch structure, facing members overlying said radially extending facesfor engagement with said opposing faces for transmitting torque andstrap members holding said facing members on said heat sink bodies, saidstrap members being located at the outer peripheral edges of said heatsink bodies and radially outward of the heat-swept area of said frictionmember and having circumferentially extending flanges at the ends foroverlapping said heat sink bodies and said facing members to resist wearand position said strap member on said outer peripheral eDges of saidheat sink body, each of said strap members extending circumferentiallyof said friction member around one of said heat sink bodies and over oneof said facing members whereby the facing members are held between thestrap member and the heat sink body.
 15. An annular friction memberaccording to claim 14 wherein said strap members are detachablyconnected at a position spaced from the ends of said heat sink bodieswhere said strap members wrap around the radially extending edges ofsaid heat sink bodies.
 16. An annular segmental friction member of abrake or clutch mechanism comprising a plurality of arcuate heat sinkbodies of heat absorbing material in end-to-end adjacent relationship,said heat sink bodies having radially extending faces for moving towardand away from opposing faces of an associated brake or clutch structure,facing members overlying said radially extending faces for engagementwith said opposing faces for transmitting torque and strap membersholding said facing members on said heat sink bodies, said strap membersbeing located at the outer peripheral edges of said heat sink bodies andradially outward of the heat-swept area of said friction member and at aposition spaced from the ends of said heat sink bodies where said strapmembers wrap around the radially extending edges of said heat sinkbodies, said strap members being detachably connected to said heat sinkbodies by fasteners extending through said strap members and said heatsink bodies and each of said strap members extending circumferentiallyof said friction member around one of said heat sink bodies and over oneof said facing members whereby the facing members are held between thestrap member and the heat sink body.
 17. An annular friction memberaccording to claim 16 wherein said facing members have radially,outwardly extending lugs disposed between said strap members and saidheat sink bodies at said positions spaced from the ends of said heatsink bodies and said fasteners extend through said lugs.